Main Source of Origin: Australia, Mexico, Ethiopia
Mohs Hardness: 6.0
There are a few different derivations of the name opal. Opal was said to be adapted from the word opalus, Latin for ‘gem’. It has also been thought to be derived from the Sanskrit, upala, meaning ‘precious stone’, and later by the Greek to be ‘opallios’, meaning ‘to see a change of color.’ The unique quality of the opal lies in its extensive play of color, where the details observed on the gemstone are often described as a sparkling rainbow or a fireworks play when viewed from different angles. In water, these gems dazzle with the opalescence of rainbow color.
Opals that are considered gem-quality are made up of spherical silicon dioxide molecules tightly packed and stacked in layers. The thickness of these layers and the diffraction of light on them gives rise to the type of colors produced by opals. Due to the types of molecular arrangement, it is common to find blue and green hue opals as compared to red hue opals.
White and Black Opals from Australia
While White opals describes a milky white body color and translucent or pastel iridescence, Black opals describes an Aurora-like iridescence against a black body color. Both White and Black opals are mined in Australia.
Water and Fire Opals from Mexico
There are also the Water opal and Fire opals. Water opal boast a clear transparent body color, whereas Fire opal shows off a red body color. Both Water and Fire opals are mined in Mexico.
Opals are soft and tend to chip easily due to its high water content. When worn as a jewelry, care must be taken to ensure the gem does not receive any heavy impact.